Mysterious Land: Discovering Illinois Land.pdf · Mysterious Land: Discovering Illinois 1...

Mysterious Land: Discovering Illinois 1

Mysterious Land: Discovering

Illinois

OVERVIEW: This group activity introduces students to six different phases in

the dramatic story of the landscape of northeastern Illinois. After analyzing

materials designed to familiarize them with each phase, students share the

information. They then discover that all of the locations were the same-Illinois!

ILLINOIS LEARNING STANDARDS

Social Science: 16, 17 Science: 12 Language Arts: 2, 4

GEOGRAPHY THEMES

Physical Characteristics of Place

Regions: How They Form and Change

NATIONAL GEOGRAPHY STANDARDS

Element: Places and Regions

Standard 4: The geographically informed person knows and understands the physical

and human characteristics of place.

Standard 5: The geographically informed person knows and understands that people

create and define regions to interpret Earth's changing complexity.

Element: Physical Systems

Standard 7: The geographically informed person knows and understands the physical

processes that shape patterns on Earth's surface.

Element: Applying Geography to Interpret the Past and Present and Plan for the

Future


Standard 17: The geographically informed person knows and understands how to

apply geography to interpret the past.

OBJECTIVES

Students will

1. analyze written materials for specific information.

2. organize information collected into a group report.

3. locate their region on a map of the United States.

4. analyze thinking processes used to form conclusions.

5. individually synthesize information into a written description.

MATERIALS

Students: One per group

Group Instruction Sheet

Assigned Group Information Sheet/s (1-6)

Notebook and pencil

Watch

Sticky Notes

Teachers:

A.1: Geologic Time Scale

A.2: Paleogeography of Illinois-Indiana Region

A.3: Time of Tropical Seas.

ADVANCED PREPARATION

1. Make six copies of the "Group Instruction Sheet" and one copy each of the six

"Group Information Sheets."

2. Make overheads of "A.1: Geologic Time Scale;" "A.2: Paleogeography of Illinois-

Indiana Region;" and "A.3: Time of Tropical Seas" for discussion.


3. Make sure you have a large wall map of the United States.

4. Look over the Group Information Sheets to familiarize yourself with the

background information and student materials.

INTRODUCING THE ACTIVITY

1. When introducing the activity, do not tell students that the activity they are working

on has anything to do with Illinois. This is a discovery they will make on their

own/with your help at the end of the activity.

2. Explain to students that they are going to be detectives and try to identify their

mystery region somewhere in the United States from the clues supplied. Their goal as

a group will be to take the information given and extract the important facts to present

to the rest of the class. When everyone has given their reports, the class will try to

deduce where their region is located in the United States.

3. Divide the class into six groups and redistribute the groups around the classroom so

that each has its own working space.

4. Pass out the "Group Instruction Sheet." Read over the tasks of the reader, the

recorder and the timekeeper. Tell students that those in the group who do not have an

assigned job will be the presenters and will be responsible for presenting their group's

report to the class.

5. Make sure they know the rules for brainstorming if they are not already familiar

with this process. a) All ideas are written down. b) No one is to critique anyone else's

idea at this point in time.

6. Give the groups time to decide who will be responsible for each task. Circulate as

they are trying to decide and if they can't make a decision, you will have to help

facilitate the decision making process. Deciding on their own is an important

cooperative skill.

7. Go over the steps they are to take as they try to distill the information in order to

answer the questions on the sheet. Once they have a number of ideas for each

question, the next step will be to begin the process of choosing the best of their ideas

for the presentation.

8. Students sometimes get so wrapped up in the brainstorming that they forget to pick

a name for their region. Remind them that they need to complete this final step.


9. Ask if there are any questions before the class starts the assignment. Deal with any

misunderstandings.

PROCEDURES

1. Assign the students an allotted period of time (15 or 20 minutes) to complete the

assignment. Remind the timekeepers that they will have to alert the group when 5

minutes are past and also when there are 3 minutes left so that the groups can decide

on a name for their region.

2. Encourage students to refer to the "Group Information Sheet" for answers to

questions about how to proceed before they ask you for help.

3. Pass out the 'Group Information Sheet" and allow the students to start. Circulate to

handle any problems within the groups and to help clarify any misconceptions. Group

2 may have trouble initially because they only have illustrations but that will not be a

handicap for long. Encourage students to use what they know about the plants/animals

on the Information Sheet to deduce the type of environment that would produce those

fossils.

4. Keep an eye on the clock. Do not say 5 minutes are up, etc., but do ask if

timekeepers are keeping track of the time.

5. When time is up, have each group in turn present their information to the class

along with the name they have chosen for their region.

Concluding the Lesson

1. When all presentations are complete, ask each group to try to identify their region

on a wall map of the United States. You may want to either give groups a short

conference time to come up with their decision or open the discussion to all the

students immediately. Have each group label a small Sticky Note with the name of

their region and place it on the map where they think it should be.

2. As they make their choices, have them point out the important clues such as

directions/references to nearby landmarks that they used to make their decisions. Have

the groups try to guess the regions in the order in which they are numbered since the

description with the most recognizable clues come from Group 6.

3. Take time to dwell on the reasons for the choices that were made. Examining their

reasoning methods helps to clarify what the processes were that led to the final

conclusion/s.


4. If students do not discover for themselves where the single mystery region is, then

you can go through the group information and point out that these are all the

landscapes of Illinois at some time in the past. Illinois has changed dramatically from

towering volcanoes to a huge inland sea to lush swamps and then to glaciers. The

most recent change has been from a land of prairies, savannas, and woodlands to the

present day landscape of cities, towns and farms.

5. Use the overheads provided to aid in discussion.

ASSESSING THE ACTIVITY

A pretest can be given in the form of an assignment that requires students to write

what they know about the landscape of Illinois. The length of the writing assignment

is optional. When students have completed the Mysterious Land activity, ask them to

again write a description of Illinois. After the second paper is graded, hand back both

papers so that students can see how much more they now know about the area. Group

grades can also be given on the report/how they worked in their groups.

EXTENDING THE ACTIVITY

If you have access to fossils of brachiopods, bryozoans, crinoids, etc. from the time

when there were ancient seas over parts of Illinois, you can use those instead of/with

the illustrations for Group 2. Also, plant fossils can be used to supplement the Group

4 information. If you do not have access to fossils, check with an earth science/

biology/geography teacher. In the Chicago area, the Field Museum has exhibits they

will loan to teachers.

Special Information

The Group Information Sheets for students have sources listed when they do not have

Illinois listed in the title. On the Group 2 Information Sheet, the fossil drawings are

from the Illinois State Museum Teacher Guide and the two pictures are from

Schuberth, pp.. The Group 6 Information Sheet is original text. See the source list

below.

REFERENCES

Schuberth, Christopher J., A View to the Past: An Introduction to Illinois Geology,

Illinois State Museum, 1986.

Runkel, Sylvan T. and Dean M. Roosa, Wildflowers of the Tall grass Prairie: The

Upper Midwest, Iowa State University Press, Ames, Iowa, 1989.


Illinois State Museum, Summer Teacher Training Field Trip Guide, 1990, Illinois

State Museum, Springfield, IL, 1990, 87.

INSTRUCTIONS FOR THE GROUP

CHOOSE:

1 person to be the reader if you have information to read.

1 person to be the time keeper.

The group has a total of __________ minutes to complete the assignment.

Let the group know when the first 5 minutes are up.

Let the group know when there are 3 minutes left.

1 person to be the recorder who is repsonsible for writing down all of the

brainstorming ideas.

The remainder of the group is responsible for presenting the information to the rest of

hte class.

READ: If you have informaiton to read, the reader should read the material through

one time aloud, and then go back and read it a second time so that everyone has a

chance to absorb all of the information.

BRAINSTORM: Using the information you have been provided, EVERONE should

help come up with some ideasfor each of the questions. Answers should be

descriptive!

QUESTIONS: Describe these characteristics:

What was the weather like in this region? (Atmosphere)

What was the land like in this region? (Lithosphere)

What kinds of people/plants/animals lived in this region? (Biosphere)

What sources of water were available for them? (Hydrosphere)

PICK: Pick 2 or 3 of the best ideas for each question making sure to give a good

DESCRIPTION for each so that the class will understand what the region you are

reporting on is like.

DECIDE: In your last few minutes, decide on a good descriptive name for your

region.

FINALLY: Share the name and description of your region with the class.


Overview

Physical Geography of the Formation

of the Many Landscapes of Northeastern Illinois

The northeastern Illinois landscape has changed dramatically over the last billions of

years. It is changed from towering volcanoes to a huge inland sea to lush swamps and

then to glaciers. Many of those former landscapes have been completely eradicated

from the surface, and their only record lies buried deep beneath the surface of present-

day northeastern Illinois. Fortunately, those changes have been unearthed by

geographers and geologists who have drilled and dug-into the land to reveal its

secrets.

Cycles like that of glaciation have left their marks on the surface of the earth and can

be recognized by those who learn to "read" the land. The changes wrought upon the

northeastern Illinois landscape by glaciers are responsible in part for the numerous

gravel and sand quarries in the region and the ridges that periodically interrupt the

predominantly flat landscape. The present day course of many northeastern Illinois

rivers flow through wide valleys cut by the torrents of meltwater produced by

retreating glaciers.

The most recent change has been from a land of prairies and wetlands to the present

day landscape of cities, towns and farms. The prairies and wetlands that were so

abundant at the time the first settlers came to ignore to the northeastern part of Illinois

are almost completely gone except in small pockets where they have been protected or

hidden from the encroachment of civilization.

The story of northeastern Illinois has been unraveled from evidence buried deep in the

earth beginning 1.5 to 1 billion years BP (Before Present). Earth was a very different

place then. The physical forces active at the time were very dramatic. There were

majestic volcanoes dotting the landscape, and clouds of super heated ash, dust and gas

reached high into the sky at times even blotting out the sun. The energy released was

sometimes as much as 10 million tons of TNT. The lava flowing down the side of the

volcano could reach initial speeds of 300 miles per hour. (Shuberth 1986,56)

After a long period of time measured in millions of years when the volcanoes were

actively growing, there followed a period of inactivity. The shattered cones stood

quietly and were deeply eroded and perhaps even destroyed altogether. Of

approximately 1 billion years BP during a second phase, intense violent activity

occurred, and volcanoes again became a major feature of the land. These volcanoes

did not erupt with the force of earlier volcanoes. The magma from these volcanoes


solidified deep beneath the earth because there was not enough force for the magna to

rise to the surface. As it solidified, the magma was changed to granite. As most of the

volcanic cones were eroded away, the grant was exposed. The landscape then became

one of granite mountains that were sometimes 1,000 feet high. (Schuberth 1986, 58)

The evidence and the rocks tell its story.

"Nothing lived on the lands. No plants nor animals, not even insects, lived in the

valleys and mountains, on the plains and plateaus, or on the volcanic cones. The land

was uniformly gray, reddish-brown, and brown wasteland --stark, barren, and empty.

Only the ferocious blasts and powerful shock waves from the erupting volcanoes

shattered the unearthly stillness." (Schuberth 1986, 58)

Around 525 million years ago, the once majestic volcanoes were eroded to rugged

hills which became the islands when they were submerged under a deepening sea that

was invading the North American continent. As this late Cambrian sea advanced and

then retreated, thick layers of sand, clay, and silt were deposited over what would one

day become northeastern Illinois. This cycle of retreat, erosion, and then a readvance

of the sea resulted in the deposition of a valuable sandstone, St. Peter Sandstone. The

formation is exposed along the Illinois and Fox Rivers near Ottawa at Starved Rock

State Park and nearly LaSalle at Matthiessen State Park. The St. Peter Sandstone

found in Illinois today marks the location of the ancient mid-Ordovician shoreline.

(Schuberth 1986, 66-67) The people of northeastern Illinois and the Illinois and

Michigan Canal region, in particular, owe many of their jobs to the rich deposits of

sand laid down during this period of inland seas.

During the Silurian time from 430 to 395 million years ago, Illinois was almost

continuously under the sea. The Silurian seas developed extensive coral reefs that

stretch from what is now the Ozark region of Missouri northeastward across Illinois,

Indiana, Ohio, westerner New York, and northern Ontario. The reefs supported a wide

variety of corals, bryozoans, brachiopods, crinoids, trilobites and nautiloids. They

were part of a bright colorful world of great beauty. The many fossil records found in

the maritime limestones that formed at that time help explain the abundant variety of

life found in the Silurian seas.

Over the next several hundred thousand years, the continent went through a long

period when it would be uplifted and then it would subside. The seas would transgress

or move over the land of northeastern Illinois and regress or move back to their

former position repeatedly as the land went through these periods of uplifting and

subsiding (see map). Southeastern Canada had a higher elevation than Illinois so river

systems from Canada flowed into Illinois. The huge delta of the ancient Michigan

River that flowed south out of Canada dumped immense sediment loads over the

lands. When the waters were not covering the land, a vast coastal swamp with lush


jungle like vegetation was formed. Those swamps were very similar to the Everglades

in Florida today, with huge trees unlike anything that grows on the lands today.

(Schuberth 1986, 86) The vast deposits of bituminous or soft coal created from the

former vegetation of these junglelike swamps would one day become an important

resource in northeastern Illinois!

Of all the cycles that the lands of northeastern Illinois went through, the ones that left

the greatest legacy to our present population are the Ice Ages. The flat lands and the

rich black soil of this part of the state can be traced directly to the glaciers. What was

it like during these glacial period? The weather was extremely cold and erratic

because of the presence of an immense frozen into the base of the glaciers gouged and

polished the land. Many of the rocks at the base of the ice were ground into fine rock

flour that was later to become the parent material for our soils. This scraping action

smoothed down the hills and filled valleys. (National Parks Service, no pp.)

Even as the ice margin melted back, it generally continued to flow, delivering and

releasing debris at its edges and forming other newer hills on the Illinois landscape.

These hills that are such a prominent feature of the northeastern Illinois landscape

today are called moraines.

Meltwater from the glacier often formed lakes either between moraine ridges or

between the moraine and the ice front. When they drained, broad, flat to lake beds or

plains remained. This city of Chicago is built on one of these flat lake beds! At times,

the meltwater released from the glacier or the lakes would break through the moraines

cutting wide channels. (See the map on the preceding page.) The valleys of the Fox,

Des Plaines, and Illinois Rivers were all cut by the torrential glacial meltwater.

(National Park Service, no pp.)

In the intervening years, the Lake Michigan Basin and, at times the entire Great Lakes

Basin, drained south through the Des Plaines-Illinois River Valley. About 11,000

years ago, the Wisconsin glacier retreated northward from the Lake Michigan Basin

for the last time, and 4000 years BP, the modern Great Lakes drainage system formed.

After that, no water from Lake Michigan flowed to the Illinois Valley until the Illinois

and Michigan Canal was dredged in the 1800's. (National Park Service, no pp.)

The landscape of northeastern Illinois when the first European settlers came was one

of prairies, wetlands and woodlands that had developed on the rich soil of the plaines

formed after the retreat of the glaciers. The best way to get a good picture of the

region and the life of the people that lived on the prairies, the predominant landscape

of northeastern Illinois, is to read first hand accounts. The following is from a letter

from Lucinda Rutherford shortly after she settled in northeastern Illinois.


"The praires here are delightful. They are from 12 to 20 miles wide, and 150 [miles]

long. Instead of the timber surrounding them, they surround the timber. At this season

they are most beautiful. The green grass has sprung up and covered the whole bosom

of these wastes and with that grass their springs up a multitude of flowers of every

hue, form, and scent. It is delightful to ride over this level land with every step

tramping those gems of nature underfoot. Their beautiful heads can be seen as far as

the eye can reach waving in the summer wind." (Runkel and Roosa 1989, 38)

The picture that Lucinda's letter paints is one of beauty and harmony, but not

everyone had the same view of the prairies. Life, for many, was neither pleasant or

easy. The prairie was intensely hot during the summer months. Their were droughts,

crop failures, and prairie fires that destroyed wheat fields causing shortages of food

during the winter months. There were hordes of biting insects that would nearly cover

the bodies of horses and riders driving both into a mad frenzy. (Runkel and Roosa

1989, 39) In deep winter, the winds blew out of the northwest, and the prairie was a

cold, hard, and cheerless place to live. Then, in late April or early May as the sun

warmed the prairie, the prairie flowers would begin to bloom. (Runkel and Roosa

1989, 40).

Today, as you wander along the roads of northeastern Illinois, you will see cities and

towns of all sizes. Farm fields fill in the spaces not occupied by towns. Occasionally

you will see patches of prairie flowers growing in abandoned cemeteries, along

railroad right-of-ways, or in protected areas like Goose Lake Prairie. Sadly, that is about all that is left of the once vast prairies that covered northeastern Illinois.

Sources

National Park Service, U.S. Department of the Interior, Ice Age Geology, Illinois and Michigan Canal

National Heritage Corridor, Brochure and text by: Illinois State Geological Survey Department of Energy

and Natural Resources, no date given, no page numbers used.

Runkel, Sylvan T. and Dean M. Roosa, Wild flowers of the Tall grass Prairie: The Upper Midwest, Iowa

State University Press, 1989.

Schuberth, Christopher J., A View to the Past: An Introduction to Illinois Geology, Illinois State

Museum, 1986.

Maps

Fentem, Arlen D.,"The Physical Environment: Landforms," Illinois a Geographical Survey, Dubuque, Iowa,

Kendall/Hunt Publishing Co., 1996.

Schuberth, Christopher J., A View to the Past: An Introduction to Illinois Geology, Illinois State Museum, 1986.


GROUP 2 INFORMATION SHEET

( _________ State museum 1990, 87)

Fossil Trilobites (Schuberth 1986, 53) Crinoid (Schuberth 1986, 73)



Sigillaria

(Schuberth 1986, 88)

Millions of years ago, this land region was located very close to the equator or a few

degrees south of it. Over millions of years, seas would form over the land and then

they would move back. This cycle would be repeated over and over again. When the

waters were not covering the land, a vast coastal swamp with lush jungle like

vegetation was formed. Those swamps were very similar to the Everglades in Florida

today. These swamps were places with huge trees unlike anything that grows on the

lands today. The Lepidodendron reached heights of a hundred feet or more with a

two-foot diameter. These scale like trees had leaves that grew as long as two feet.

Another tree, the Sigillaria, grew to a hundred feet with a diameter up to 6 feet. It

resembled the modern palm tree. Gigantic rush like plants flourished in these swamps

along with other smaller plants that formed the underbrush. (Schuberth 1986, 86-87)

"As the luxuriant plant growth of such a swamp dies, it falls into the water-logged

soil. The water, and rapid burial by the quick addition of falling leaves, protect the


twigs, branches, leaves, fruits, and seeds from...decaying. As plant material continues

to accumulate, it gradually turns to peat, a porous brown mass of organic matter in

which twigs, roots, and other plant parts can still be recognized. With further chemical

transformations of the aging organic matter, the plant carbon becomes more

concentrated and the peat turns into lignite-a soft coal like material. Greater depth of

burial, still more time, and higher temperatures may further change the lignite to

bituminous or soft coal." (Schuberth 1986, 94) The coal created from the former

vegetation of these jungle-like swamps would one day become an important resource

in this region!

"A Pennsylvania coal-forming swamp reconstructed as a living biome. Our valuable

coal reserves developed from swamps such as this." (Schuberth 1986, 90)



Jefferson's mammoth (Schuberth 1986, 146)

American Mastodon (Schuberth 1986, 147)


The generally cold and unsettled weather resulted from the presence of the ice sheet" that in the

winter looked "like a huge, broad ramp covered...with a new coat of white snow." While the

winters were much warmer than today, the summers were also much cooler than today. The

weather was persistently cloudy and cool with abundant rain and occasional snow. During the

summer, clouds of mosquitoes and black flies probably swarmed.

Very near the glacier, the climate was too harsh for any trees to grow. The barren landscape

stretched for 50 miles in some places. South of the tundra-like zone, the sparse and scattered

clumps of spruce and fir gradually turned into a continuous evergreen forest. The wooly

mammoth roamed within walking distance of the ice front. The mammoth was a short-tailed and

small-eared relative of the elephant with a wooly coat that made him well equipped for the

rugged climate along the glacial front. The immense tusks of some of the older mammoths were

used as snowplows to clear the snow cover from bushes so they could feed. Just beneath the skin

was a layer of fat two or three inches thick that made it possible to survive the winter when food

sources were snow-covered. The American Mastodon another mammoth-like animal browsed on

the coniferous forests southwest of the glacier. The giant beaver that weighed about 500 pounds

and the stag-moose with antlers that often measured 6 foot across also inhabited th forests.

Some people believe that the Clovis people (the first people known to have inhabited this great

land) may have lived in the vicinity and hunted these gigantic animals. Spear points or other

projectile points found near the fossilized bones of mastodons leads some experts to believe that

the Clovis people may even have been partially responsible for the disappearance of many of

those now extinct species.

(Schuberth 1986, 142-151)



A letter from Lucinda Rutherford shortly after she settled in eastern _.

"The prairies here are delightful, they are from 12 to 20 miles wide, and 150 miles long, instead of the

timber surrounding them, they surround the timber, at this season they are most beautiful. The green grass

has sprung up and covered the whole bosom of these wastes; with that grass there springs up a multitude

of flowers of every hue, form, and scent. It is delightful to ride over this level land and every step,

tramping those gems of nature underfoot. Their beautiful heads can be seen as far as the eye can reach

waving in the summer wind."

To most, life on the _____ prairies was neither pleasant nor easy. The hordes of biting insects that lived

on the prairie would alight on and nearly cover the bodies of horses and riders driving both into a mad

frenzy....quite often there were no trees or other landmarks to guide the settlers across these vast plains.

On the prairie it was intensely hot during the summer months, and bitterly cold during the winter.

Droughts caused crop failures and prairie fires destroyed wheat fields, which resulted in shortages of food

during the winter months for some families. Other families did not arrive in time to plant and raise

crops....a Sangamon County family near starvation was described rather graphically by Peter Cartright, a

Methodist circuit rider, in the winter of 1845: "For many miles back I had not passed a solitary house, but

right here was a little, old, smoky cabin, and a poor, dirty, ragged family, hovering and shivering over a

small fire. The man, the head of the family, was gone out hunting. I was hungry, and asked for food; but

the good woman informed me she could not give me anything to eat, for the best of reasons, they had

nothing for themselves.

Tall grass prairie is a bittersweet thing. In deep winter when the long winds blow out of the northwest, the

prairie world can be ... cold, hard, and cheerless... And then, suddenly, all that begins to change. ...The

annual prairie miracle is underway... There is a rich, loamy sweetness to the air as the sun warms the deep

prairie soils and life begins to emerge from winter hiding. A faint wash of green appears on the gray-dun

prairie landscape and then, on some fine day in late April or early May, the first real splashes of floral

pigments are added. From then until hard frost, there will be no time when the prairie is without flowers.

In wave after wave of floral successions in indigo, pale lavender, crimson, gold, cream, white, and

magenta-in every tone and hue of the artists' palette-the prairie flowers come on. For 6 months or more

the rich and varied panorama will continue, changing from week to week, beginning with ground-hugging

pasque flowers and birdsfoot violets and climaxing with towering suflowers. Many of their names are

pure Americana: rattlesnake master, bundle flower, queen-of-the-prairie, shooting star, blazing star, alum

root, blue-eyed grass, yellow star-grass, bell flower, windflower, ... butterfly milkweed, and button

snakeroot. (Runkel and Roosa 1989, 36-42)



In this region, there are a variety of cities and towns. Some of them, like the city on the lake in

the northeastern part of the area, are heavily populated. The downtown area of this large city has

a lot of very tall skyscrapers. As a matter of fact, when you are walking on the streets downtown,

you sometimes feel as if you were in a forest made up of buildings. There are many express-

ways running into the large downtown area from the surrounding suburbs. These suburbs contain

almost as many people as the city itself. At certain times of the day, there are so many cars on the

expressways that traffic sometimes comes to a complete stop. The skyline at night as you drive

into the city is beautiful with many of the tops of the downtown skyscrapers lit up with colorful

lights.

There are many restaurants, theaters, shopping areas, businesses, and industries within the city

and the suburbs. They are necessary to supply jobs, food, merchandise and recreation for the

huge population that lives there. This city is built along a river and a lake and both the rich and

the poor can enjoy the waterfront parks and beaches. A green belt of forest preserves where

people can go to enjoy nature encircles the city.

You can find all types of people living in this city. There are rich, middle-class and poor people.

Many of them come from other countries and have moved to this city to make it their home.

There are many different types of homes for people to live in. In some neighborhoods, people

live in a house with their own yard; in others, people live in apartments. Many neighbor-hoods

are a mixture of houses and apartments. Sometimes, the people are crowded together and the

living conditions are very poor.

Other cities are spread out over the countryside. Some have large populations with a lot of

industries and businesses. Some towns in this special region are rural and are much smaller.

They are surrounded by small family owned farms and by larger farms operated by companies.

In the summertime, the fields have crops. In the wintertime, these barren fields stretch for miles

and are sometimes covered with snow.

There are many places for people in these small towns to go for recreation. The plentiful rivers

and streams are busy places for recreational boaters and fishermen. There are parks with wooded

areas for hiking and exploring. Other trails run along the site of an old Canal and rivers and are

used for biking and hiking.

The waterways have historically been a major transportation route. Barges use the river to move

coal, chemicals, and grain to markets. Canals connect waterways. Locks and dams built on the

major rivers help barges maneuver up and down its length. These water highways have been

responsible for the birth and growth of cities, large and small, along their banks.


A.1: Geologic Time Scale


The geologic time scale for North America showing the approximate age and duration

of each era, period, and epoch. The ages are in millions of years. Periods and epochs

missing in Illinois are shaded. (Schuberth 1986, 69)

A.2: Paleo Geography of Illinois-Indiana Region

Paleogeographic map of the Illinois-Indiana region during Pennsylvanian time. The

Michigan River was building a delta into the shallow sea to the south. While sand,

silt, and lime were accumulating in the sea, coastal swamp forests flourished on the

adjacent lands. The plant debris that accumulated as thick mats of peat eventually

turned into bituminous coal. (Map courtesy of Illinois State Geological

Survey) (Schuberth 1986, 87)


A.3: Time of Tropical Seas

This coral reff flourished in the Silurian sea and is reconstructed on the basis of fossil

evidence. Corals, such as the large, rounded reef-building tabulates, were especially

common. so, too, were the flower-shaped, filter feeding crinoids and trilobites try to

escape from the taper-shaped, tentacle-bearing nautiloid cephalopods that were the

primary predators oon the reef. As in moder coral reefs, the organisms living during

Silurian time were bright and colorful. (Photograph courtesy of Milwaukee Public

Museum) (Schuberth 1986, 54)

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